Department of Physics, Emory University, Atlanta, Georgia 30322, USA.
Department of Physics, University of Muenster, 48149 Muenster, Germany.
Nat Nanotechnol. 2014 Jul;9(7):509-13. doi: 10.1038/nnano.2014.88. Epub 2014 May 11.
Magnonics is based on signal transmission and processing by spin waves (or their quanta, called magnons) propagating in a magnetic medium. In the same way as nanoplasmonics makes use of metallic nanostructures to confine and guide optical-frequency plasmon-polaritons, nanomagnonics uses nanoscale magnetic waveguides to control the propagation of spin waves. Recent advances in the physics of nanomagnetism, such as the discovery of spin-transfer torque, have created possibilities for nanomagnonics. In particular, it was recently demonstrated that nanocontact spin-torque devices can radiate spin waves, serving as local nanoscale sources of signals for magnonic applications. However, the integration of spin-torque sources with nanoscale magnetic waveguides, which is necessary for the implementation of integrated spin-torque magnonic circuits, has not been achieved to date. Here, we suggest and experimentally demonstrate a new approach to this integration, utilizing dipolar field-induced magnonic nanowaveguides. The waveguides exhibit good spectral matching with spin-torque nano-oscillators and enable efficient directional transmission of spin waves. Our results provide a practical route for the implementation of integrated magnonic circuits utilizing spin transfer.
磁振子学基于通过在磁性介质中传播的自旋波（或其量子，称为磁振子）进行信号传输和处理。就像纳米等离子体利用金属纳米结构来限制和引导光学频率等离子体激元一样，纳米磁振子学利用纳米尺度的磁性波导来控制自旋波的传播。最近在纳米磁学领域的进展，如自旋转移力矩的发现，为纳米磁振子学创造了可能性。特别是，最近已经证明纳米接触自旋扭矩器件可以辐射自旋波，作为用于磁振子应用的局部纳米尺度信号源。然而，自旋扭矩源与纳米尺度磁性波导的集成，对于实现集成的自旋扭矩磁振子电路是必要的，但迄今尚未实现。在这里，我们提出并实验证明了一种利用偶极场诱导的磁振子纳米波导实现这种集成的新方法。这些波导与自旋扭矩纳米振荡器具有良好的光谱匹配，并能够有效地定向传输自旋波。我们的结果为利用自旋转移实现集成磁振子电路提供了一条实用途径。
